[Samba] 4.1.7 Server Side Copies & Disk Permissions

[David Disseldorp]

Hi Stuart,

On Tue, 22 Apr 2014 09:41:16 +0100, Stuart Naylor wrote:

> As soon as I add the declaration for server side copies I hit problems with disk permissions.

FWIW, server-side copies are enabled by default since Samba 4.1.0. The
vfs_btrfs module only changes how such requests are handled by the
smbd file-server.
For details, see https://wiki.samba.org/index.php/Server-Side_Copy

> Same as in 4.1.6 and always the same so I will not bother to add a log.
> 
> If you follow http://wiki.samba.org/index.php/Setting_up_a_home_share
> 
> But have vfs objects = btrfs declared all is different.
> 
> You can add users and groups but the default Everyone,  CREATOR GROUP and a Unknown you just can't delete them.
> 
> As soon as you press apply then they are back again.

I expect this is due to the POSIX to Windows Access Control List mapping
behaviour. The Owner, Group and Other entries are always present in a
POSIX ACL. Samba maps these entries to NT ACL entries on retrieval.

The vfs_btrfs module doesn't intercept ACL retrieval/manipulation
requests, so you shouldn't see any difference from the default VFS in
this regard.

If you are seeing a difference, then please provide (level 10) debug
logs and corresponding network traces taken with and without vfs_btrfs
enabled.

Cheers, David